Injury of Rat Peritoneal Mast Cells in Vivo by Staphylococcal Alpha Hemolysin and Leukocidin

Intraperitoneal injection of rats with purified staphylococcal alpha hemolysinor leukocidin in saline results in mast cell injury. Injection of alpha toxin produces an increase in the mast cell content of the peritoneal fluid, congestion of mesenteries and intestines, the appearance of large vacuoles in mast cells, and increases in acid phosphatase and esterase activities. This suggests lysosomal damage in mast cells and injury of small peritoneal vessels. Leukocidin also causes mast cell injury which is manifested above all by degranulation and the appearance of numerous small vacuoles. The percentages of cells with acid phosphatase and esterase activities aresimilar to those obtained for the control group. Cytological changes observed in mast cells after leukocidin injection are of the same type observed after the use of surface active agents which damage the cellular membrane.